public static bool HasFooter(GBAROM rom)
{
Stream stream = rom.GetStream();
stream.Seek(-12, SeekOrigin.End);
bool result = true;
using (BinaryReader reader = new BinaryReader(stream))
{
int length = reader.ReadInt32();
int signature = reader.ReadInt32();
uint crc32 = reader.ReadUInt32();
result = signature == 0x1270D1FE;
}
return result;
}
public static void RemoveAndReadFooter(GBAROM rom, GBAMemoryManager memMan)
{
Stream stream = rom.GetStream();
stream.Seek(-12, SeekOrigin.End);
int length;
uint crc32;
using (BinaryReader reader = new BinaryReader(stream))
{
length = reader.ReadInt32();
int signature = reader.ReadInt32();
crc32 = reader.ReadUInt32();
if (signature != 0x1270D1FE)
{
throw new Exception("No footer present");
}
stream.Seek(12 + length + 12, SeekOrigin.End);
byte[] version = reader.ReadBytes(12); //Like we care
while (stream.Position < stream.Length - 12)
{
byte[] rawid = reader.ReadBytes(4);
string id = new string(Array.ConvertAll(rawid, Convert.ToChar));
int chunkLength = reader.ReadInt32();
if (id == "Free")
{
long endOffset = stream.Position + length;
int offset = 0;
while (stream.Position < endOffset)
{
int relativeOffset = reader.ReadEncodedInteger();
offset += relativeOffset;
int freeLength = reader.ReadEncodedInteger();
memMan.AddManagedSpace(offset, freeLength);
offset += freeLength;
}
}
else
{
stream.Seek(chunkLength, SeekOrigin.Current);
}
}
}
rom.Length -= 12 + length + 12; //Remove footer
}
